Spinosaurus
Spinosaurus was a large theropod dinosaur that is known to be the prime candidate for being the largest known land carnivore yet, possibly being larger than Tyrannosaurus, Carcharodontosaurus, and Giganotosaurus. Information Currently, Spinosaurus is only known from several poor, incomplete and extremely fragmentary specimens. The holotype specimen was discovered in 1912 in Egypt, by German paleontologist Ernst Stromer. The specimen included the lower jaw, teeth, several neural spines, ribs, vertebrae and a single phalanx. But this holotype was destroyed after the museum, where the fossils were displayed at, was destroyed by Allied forces during the night of 24/25 April 1944. Stromer measured the maximum length of Spinosaurus as 12 meters, despite the holotype measuring only about 10 meters long. Newer discoveries from Tunisia in 1999 and Morocco in 2005 and 2014 suggest that Spinosaurus may have reached 15 meters in length. A size estimate by Dr. Dal Sasso suggests that the animal could have capable of reaching a length of 18 meters, albeit it is not certain. Later research confirmed this as the estimations gave it a size greater than 15 meters. Ibrahim and Sereno made a new reconstruction of this animal in 2014, suggesting that Spinosaurus may have had a quadrupedal posture. However, this reconstruction has been criticized by both the public and the scientific community; although some people and scientists support it, some people (including scientists) believed it to be a chimera or error by Ibrahim due to an error in the original paper's description of how the measurements were done, including Scott Hartman & John Hutchinson. A new revision has been published which supports Ibrahim's measurements. Evers et al. 2015 argued that Sigilmassasaurus was a distinct genus, and therefore doubted whether the material assigned to Spinosaurus by Ibrahim et. al. even belonged to it. Spinosaurus was once thought to be a semi-aquatic animal. This was suggested by its elongated feet, hydrodynamic design, and sensors in the form of small holes on the top of its snout. They were perfect for locating fish in the water. This was found when in 2010 an isotope analysis by Romain Amiot and colleagues found that oxygen isotope ratios of spinosaurid teeth, including teeth of Spinosaurus, indicate semiaquatic lifestyles. However these speculations has lately been fallen out of favor. Spinosaurus’ primary weapon is its mighty 5 foot arms with 25-30 centimeter fingers armed with 15-20 centimeter claws, designed for killing and occasionally for walking. The arm would swipe at another predator causing the claws to dig extremely deep into the flesh while the fingers are just an extension, like a knife has a handle, making the claw go deeper into the prey or competitor causing great pain. Then, its secondary weapon is its specialized 1.6 meter jaws. These jaws are designed for grabbing the prey, clamping down and suffocating it and they are most similar to these of crocodile. Scientists guess that it used them like a crocodile, to throw prey from side to side and tearing them into smaller 'pieces'. The jaws also had conical teeth like today's crocodiles. The teeth were hollow and designed for fish hunting, meaning it had a relatively weak bite compared to other predators but is able to kill all the same. The enlarged vertebrae of Spinosaurus that give it its name have been a cause of a great deal of controversy in recent years, with some people claiming they were a shrink-wrapped sail akin to Dimetrodon or Edaphosaurus and others arguing instead that it was a thick ridge or hump akin to a bison or rhinoceros. The remains published in 2014 have shown that the vertebral spines narrow at the top nearer the front end of the animal, which means they would not have supported a thick fatty hump, however, they still do not display the characteristics of a “true sail-back” either. There were "few channels for blood vessels" meaning it likely wasn't for thermal regulation. Sail-backed reptiles have thin supports for their sails, almost like the fins of a fish, whereas the vertebrae of Spinosaurus are thick at the base and narrow towards the top. In life the structure would have risen from the body to form a triangular shape over the animals back (when viewed from in front), as opposed to either a shrink-wrapped sail or a large hump. However, the vertebrae towards the animal's hips were thicker and could have supported a hump, perhaps to aid in buoyancy or balance. In-Game Spinosaurus will be released in the full game of Prehistoric Kingdom. It is depicted with crocodilian-like osteoderms, a half hump at the base of its famous sail, and a stylized head crest. Category:Dinosaurs Category:Carnivore Category:Theropod